Non-Gaussian Velocity Distributions in Solar Flares from Extreme Ultraviolet Lines: A Possible Diagnostic of Ion Acceleration

The astronomer's dilemma, detailed in a tasteful array of colors: how in the world do we disentangle the 3D microphysics of an object anywhere in the cosmos (except for a basement laboratory), for which we only have 2D information? One partial answer is to add the dimension of spectral distribution, thus reducing the problem of mappying 3D into 2D to a different problem of mapping 4D into 3D. Here it's about line widths of optically-thin EUV emission lines from a solar flare, and the cartoon nicely illustrates various possibilities. No other cartoon in this Archive currently deals with issues like these, although theorists have full liberty to sketch complicated microphysics at will. Sometimes this sketching just leads to bubbles or even double bubbles..